Inertia actuated propeller control valve



2 Sheets-Sheet 1 QavERA/aR M o \KV/ i1 INVENTOR4 Er]? MIPZZI'IZ I BYATTQ RNEY April 18, 1944. 5.; MARTIN INERTIA ACTUATED PROPELLER CONTROLVALVE Filed April 24, 1941 .Tm M 2 V////// -m .mW l/ a". v M annual m MPm MM g a a B n Q WW E z a rm 7.? Q

E. MARTIN April 18, 1944.

INERTIA ACTUATED PROPELLER CONTROL VALVE Filed April 24, 1941 2Sheets-Sheet 2 IIIII 4m m M i E4 Patented Apr. 18, 1944 UNITED STATESPATENT OFFICE 2,346,856 msa'rm sc'rua'mn rnorsnnsncon'raor.

, VALVE Eric Martin, West Hartford. Conn., assignor to .United AircraftCorporation, East Hartford,

Conn, a corporation of Delaware Application April z4,1941, SerialNestor" Claims. (01.170-163) This invention relates to improvements incon trolmeans for governor controlled controllablepitch propellers andhas particular reference to a device for anticipating the pitchcontrolling menting the operation of the governor in controlling thepitch or the propeller.

Other objects and advantages will be more particularly pointed outhereinafter or will become apparent as the description proceeds.

In the accompanying drawings, in which like reference numerals are usedto designate similar parts throughout, there is illustrated a suitablemechanical embodiment for the purpose of disclosing the invention. Thedrawings, however, are for the purpose of illustration only and are notto be taken as limiting or restricting the invention since it will beapparent to those skilled in the art that various changes in theillustrated construction may be resorted to without in any way exceedingthe scope of the invention.

In the drawings,

Fig. 1 is a longitudinal cross-sectional view of a governor anticipatingdevice constructed ac- Fig. 7 is a transverse sectional view similar toFig. 4 showing the relative position of the parts when in theiroperative position, and

Fig. 8 is a transverse sectional view on the line 0-8 of Fig. 1.

Referring to the drawingsin detail, the numeral ill generally indicatesan engine driven speed responsive governor which is schematically shownin the drawings but may be any of various forms well known to the priorart. A suitable governor is particularly illustrated and described inUnited .States Patent No. 2,204,640, issued June'l8, i940, to Elmer E.Woodward, for Governor mechanism.

This governor is supplied with hydraulic fluids from some suitablesource such as the engine lubricating pump l2 and may include a boosterpump for raising the oil pressure above thepressure at the outlet of thelubricating pump l2. The

governor outlet is connected through a fluid line it with one side ofthe pitch changing motor ll of a controllable-pitch propeller generallyindicated at IS. The propeller indicated generally at it may be of anyof several forms well known to the prior art, a suitable form beingparticularly 1115-:

trated and described in United States Patent No. 2,174,717, issuedOctober 3, 1939, to Frank W. Caldwell, Erie Martin and John E. Anderson,for Multiposition controllable pitch propeller.

This propeller is so arranged that application by. the governor ofhydraulic fluid to one side of the pitch changing motor will operate themotor to increase the propeller pitch while a governor action relievingthis pressure will permit the pitch cording to the invention, theconnection of the device with a governor and a controllable-pitch propller being schematically illustrated.

Fig. 1a is a schematic view of an alternative arrangement oi the boosterpump.

Fig. 2 is a transverse sectional view on the line 2-2 of Fig. 1 showingthe position of the parts when in their neutral or inoperative position.

Fig. 3 is a transverse sectional view on the line 3-3 of Fig. 1 showingthe position of the parts when in their neutral orinoperative position.

Fig. 4 is a transverse sectional view on theiine 4-4 of F g. 1 showingthe position of the parts when in their neutral or inoperative position.

Fig. 5 is a transverse sectional view similar to Fig. 2 showing theposition of the partswhen in their operative position.

Fig.6 is a transverse sectional view similar-to Fig. 3 showingtherelation of the partswhen in 7 their operative position.

to decrease.

Intercepting the line it between the governor and the propeller there isan acceleration responsive propeller pitch control device, generallyindicated at 20. The device 20 comprises a casing Hhaving a base or padportion 24 adapted to be mounted upon the propeller driving engine, anengine driven drive shaft 26 extending through a bore in the base 24 andthe portion of the casing I adjacent thereto and into a chamber providedin the end of the casing opposite the base. an inertia member 28 drivenby the shaft 26 through the intermediacv of a resilient connection inthe form of a spring 30, and a valve member 32 rigidly secured totheinertia member 23 by means including the key 29 and extending throughan enlarged tubular portion of the drive shaft 26. The sprin 30resiliently retains the members 26 and 32 in therelative position inwhich the tongues 3i on the member 26 projecting into the slots 33 inthe member 32 are held at one end of the respective slots and acts aspositive limit stops for determining the normal relative position-oithese two The drive shaft 2! is provided with three setsoflonlitudinallyspacedportslhflandtland the casing 22 is provided withcorresponding annular chambers ll, 42 and M surroimding these'ports. Thevalve member I! is provided with ports It positioned to register withthe ports 34 when the device is rendered operative to anticipatethe'action of the governor, with ports It positioned to normallyregister with the ports 30, and with elongated ports or cut-awayportions I which register at all times with the ports 38, The governorend of the line It is connected with the annular chamber 44 leading tothe ports ll and It and the propeller end of this line is connected withthe chamber l2 and the ports as and cut-away portion ll of the valvemember, A source of fluid under high pressure, such as the pump l2,"which ma be, as shown in Fig. 1a, the governor booster pump shown in theWoodward patent referred to above, is connected through a fluid line Itwith the chamber 40 and the ports 34 and it. The valve member 32 isclosed at both ends and provided with an internal bore [I which connectsthe various sets of ports ll, II and 4' v provided therein. This memberis rotatable relative to the drive shaft upon rotation of the inertiamember 28 relative to the drive shaft to change the registry of theports 4' and I. in the valve member with the corresponding ports as andIt in the drive shaft. This relative rotation of the valve member 32with respect to the drive shaft is provided for by the flexibility ofthe elastic coupling and maybe facilitated by the assasse which theports and u are brought into mutry and the ports it and 38 are moved outof thereby blocking of! the governor end of the fluidline it. With thisrelative position of the parts is and :2 the line as is connectedpropeller pitch and reduce the speed of the engine and propeller aconsiderable time before the governor would have had time to accomplishthis responsive device will retard abrupt changes in the speed of theengine-propeller combination 4 which would place undue strains on thepropeller provision of an anti-friction bearing, such as indicated at.It, between the inertia member and the drive shaft. I

- Operation 7 When the engine and propeller are operating within apredetermined range of torsionalaccel- ,eration the governor anticipatorremains inoperative and the drive shaft II and drive member 32 occupythe relative position particularly shown in Figs. 1, 2, 3 and 4 locatedby cohtact of the tongues 3| with the ends of the slots 18 to which theyare resiliently urged by the spring II. In the relative position of thedrive shaft and valve member indicated, the ports 48 are out of registrywith the ports II, as is particularly illustrated in Fig. 2, so that thehigh pressure fluid line It leading to the anticipator is'blocked, theports 3| remain open, as is particularly illustrated in Fig. 8, and theports 48 register with the ports 3! so that the governor end or thefluid line it is connected with the internal bore It of the valve memberand through this bore and the ports 3' with the propeller end or theline ll. Thus, when the engine and propeller are operating within thepredetermined range oi torsional acceleration mentioned above, the speedresponsive governor is continuously connected with the propeller tocontrol the same in accordance withthe constant speed setting of thegovernor and the acceleration responsive device does not affect thepropeller pitch. If, however, the predetermined range of torsionalaccelerations is exceeded in a positive P rts in said drive shaft andsaid valve member.

direction, 1. e., if the speed suddenly increases, the

spring I. will wind up to a certain extent thereby permitting the driveshaft it to'rotate relative to the inertia member is and the valvemember 32. This relative rotation will bring the drive' shaft and thevalve member to the relaflve podtion particularly illustrated in Figs.5, 6. and 7 in and the engineor which might result in seriousoverspeeding of the combination in the event the engine throttle wassuddenly moved from a relatively retarded position to a high poweroutput position.

While a suitable mechamcal arrangement has been hereinabove describedand illustrated in' the accompanying drawings for the P pose ofdisclosing the invention, it is to be understood that the invention isnot limited to the particular arrangement s0 illustrated and describedbut that such changes in the size, shape and arrangement of the variouspartsmay be resorted to as come within the scope or the subioinedclaims.

, Having now described the invention so that I others skilled in the artmay clearly-understand thesame,whatitis desiredtosecurebyletters Patentis as follows:

1. In combination with a hydro-controllable propeller, a speedresponsive hydraulic governor for controlling the pitch changes otsaidpropeller. a fluid line between said governor and said pro- -peller, anda source of fluid under pressure, an

acceleration responsive device intercepting said fluid line between saidgovernor and said propeller and having a connection with said source offluid under pressure, said acceleration responsive device comprising, adrive shaft, a rotatable valve member operatively associated with saiddrive shaft, a rotatable inertia member carried by said drive shaft andconnected with said valve member, a flexible connection between saiddrive shaft and said inertia member, and registerable operative tomaintain said governor connected with said propeller as long as the rateof change A of propeller speed does not exceed a predetermined limit andto disconnect said governor from said propeller and connect saidpropeller directly with said source of fluid under pressure if saidpredetermined limit is exceeded.

2. An acceleration responsive speed controlling device comprising, ahollow drive shaft having fluid passage ports therethrough, a'hollowvalve member in said drive shaft having ports regis- I terable with theports in said driveshaft said ports being divided into three sets onlytwo of speed proportional to which can-be brought into registry at thesame time, an inertia member connected with said valve member, and aflexible spring driving connection 7 between said drive shaft and saidinertia member wherebysaid valve member mayrotate relative to said driveshaft under the influence oiacceleration rorces to change the registryof said ports when said acceleration'iorces exceed a predeterminedlimit.

3. In a'power plant speed control apparatus, a power actuated speedvarying device, a first power line leading to said power plantacceleration forming part orsaid first power line, a speed governor alsointercepting said first power line and normally cont lling the operationof said speed varying devi e, a second power line leading to saidacceleration actuated device, said acceleration actuated device normallymaintaining said second power' line closed but actuated by accelerationwhen the power plant acceleration exceeds a predetermined value toconnect said second power line with said speed varying device and bypasssaid governor.

device. a device actuated by 4. In a power plant speed controlapparatus,

a power actuated speed varying device, and means for controlling saidspeed varying device comprising a first power line, a speed governorintercepting said first power line and normally controlling theoperation vice, a second power line, and an acceleration responsivedevice connected with said speed varying device and intercepting both ofsaid power lines operative to maintain said first power line openedandsaid second power line closed as long as the power plant accelerationremains below a predetermined value within the re latory capacity ofsaid speed governor, and to of said speed varying despeed governor "I.In a speed control apparatus for a power I plant including acontrollable-pitch propeller, a

fluid motor carried bysaid propeller and operative to change thepropeller pitch, a first pressure fluid line leading to said motor, aspeed governor intercepting said first pressure fluid line andcontrolling the operation oi said motor, a second pressure fluid line,and an acceleration responsive device intercepting botho! said pressurefluid lines operative to maintain said first pressure fluid line openand said second pressure fluid line closed as long as the power plantacceleration remains below a predetermined value within the regulatorycapacity of said speed governor and to close said first pressure fluidline and connect said second pressure fluid line with said propellerwhenever the power plant acceleration exceeds said predetermined value,and means for supplying fluid under pressure to each 0! said pressurefluid lines. t,

8. Ina speed control for a power plant, a load varying device operativeto cdntrolthe Dower plant speed, afirst source of power connected closesaid first power line and open saidsecond power line whenever the powerplant acceleration exceeds said predetermined value.

5. In combination with a load varying device operative to change thespeed oi a power plant, and a centrifugal governor device driven at athe speed of said load varying device and varying action of said loadvaryin device to maintain the speed of said device substantiallyconstant, an acceleratio responsive inertiadevice separate from saidgovernor, responsive to acceleration of said varying device andoperative-at values of acceleration of said load varying device above apredetermined value, and means operated by said inertia device totemporarily disconnect said centrirugal governor and separately controlsaid load varying device.

6. In a speed control apparatus tor a power plant including acontrollable-pitch propeller, means ior' controlling said propellercomprising, a motor carried by said propeller and operative to changethe propeller pitch, a first power line, a speed governor forcontrolling the operation oi said motor intercepting said flrst powerline, a second power line,- and an acceleration responsive deviceconnected with said propeller and intercepting' both of said power linesoperative to maintain said first power line open and said second powerline closed as long as the power plant acceleration remains below apredetermined value within the regulatory capacity of said operative tocontrol the load load varying device, and iii-- terposed between saidgovernor and said load connect said source oi power with said propeller"with said load varying device, a speed governor interposed between saidfirst power source and said load varying device, a second source ofpower, and an accelerationactuated device interposed between saidspeed'governor and said load varying device and between said secondpower source and said load varyin device and operative upon a change inpower plant speed in excess of a predetermined rate to discontinue theconnection between said speed governor and said load varying device andopen a connection between said second power source and said load varyingdevice to vary the load and'oppose the change inspeed.

9. In combination, a controllable-pitch propeller, aspeed responsivegovernor operatively connected with said propeller for normallycontrolling the pitch oi. said propeller to maintain substantiallyconstant propeller speed, a source of power, acceleration actuatedmechanism, connected-with said source of power, located in theconnection between said governor and said propeller, and operable'byacceleration of said propeller above a-predetermined amount to disconnect said governor from said propeller and to to check said accelerationby increasing the propeller pitch. 1

10. In combination, a controllable-pitch propeller, a speed responsivegovernor operatively connected with said propeller iornormallycontrolling the pitch of saidpropeller to maintain substantiallyconstant propeller speed, a source of power. means connectingsaid-source of power with said'propeller comprising accelerationactuated mechanism having means normally blocking the connection betweensaid source of power and said propeller, and operable by acceleration.

- or said propeller above a predetermined amount to disable saidblocking means and connect said source oiipower with said propeller todirectly control saidpropeller and temporarily discon-,

tinue the control operation or said governor.

and to close'said flrst powerline

